XADMaster/XADLArcHandles.m
2018-03-21 14:24:50 +02:00

86 lines
2.2 KiB
Objective-C

/*
* XADLArcHandles.m
*
* Copyright (c) 2017-present, MacPaw Inc. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301 USA
*/
#import "XADLArcHandles.h"
@implementation XADLArcLZSHandle
-(id)initWithHandle:(CSHandle *)handle length:(off_t)length
{
return [super initWithInputBufferForHandle:handle length:length windowSize:2048];
}
-(int)nextLiteralOrOffset:(int *)offset andLength:(int *)length atPosition:(off_t)pos
{
if(CSInputNextBit(input)) return CSInputNextBitString(input,8);
else
{
*offset=(int)pos-CSInputNextBitString(input,11)-17;
*length=CSInputNextBitString(input,4)+2; // TODO: 3 or 2?
return XADLZSSMatch;
}
}
@end
@implementation XADLArcLZ5Handle
-(id)initWithHandle:(CSHandle *)handle length:(off_t)length
{
return [super initWithInputBufferForHandle:handle length:length windowSize:4096];
}
-(void)resetLZSSHandle
{
flagbit=7;
for(int i=0;i<256;i++) memset(&windowbuffer[i*13+18],i,13);
for(int i=0;i<256;i++) windowbuffer[256*13+18+i]=i;
for(int i=0;i<256;i++) windowbuffer[256*13+256+18+i]=255-i;
memset(&windowbuffer[256*13+512+18],0,128);
memset(&windowbuffer[256*13+512+128+18],' ',128-18);
}
-(int)nextLiteralOrOffset:(int *)offset andLength:(int *)length atPosition:(off_t)pos
{
flagbit++;
if(flagbit>7)
{
flagbit=0;
flags=CSInputNextByte(input);
}
int byte=CSInputNextByte(input);
if(flags&(1<<flagbit)) return byte;
else
{
int byte2=CSInputNextByte(input);
*offset=(int)pos-byte-((byte2&0xf0)<<4)-18;
*length=(byte2&0x0f)+3;
return XADLZSSMatch;
}
}
@end